(LATEST) Updated the people.html file for certain GCSC entries

[SaptSinha]

Name and Institution (Required)

Name: Saptarshi Sinha Institution: Washington University in St. Louis

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• [x] Contributing guidelines

Describe the update

Per Randall's request, I corrected some of the prior GCSC entries and added a few new ones. NOTE: I submitted a pull request earlier but had to close it, and deleted the corresponding branch. Please ignore any email/pull request you may have received for the branch _people_August_42023.

Expected changes

The GCSC entries, both in the map and in the information section, would be updated upon merging.

Related Github Issue(s)

Not applicable.

[SaptSinha]

Opening a new PR and deleting this one and its branch due to re-submission errors & for incorporating more changes ....